| The first improvements on nature's design | | | | a stone prior to cutting. Â Cleaving: |
| involved a polishing of the crystal faces, | | | | Cleaving refers to splitting a stone along |
| which was called the "Point Cut". As further | | | | its grain by striking it. A rough stone is |
| refinement progressed, one half of the | | | | cleaved if there are conspicuous defects and |
| crystal would be cut off, creating the "Table | | | | or inclusions which would prevent it from |
| Cut". At the time, diamonds were valued | | | | being made into a single gemstone. Cleavage |
| primarily for their luster and hardness. | | | | is the tendency of crystalline materials to |
| Table Cut diamonds appeared black to the eye. | | | | split along definite planes. Due to its |
| The Modern Round Brilliant cut (below) is the | | | | atomic structure, a diamond can be cleaved in |
| culmination of several hundred years of | | | | four directions parallel to each of the four |
| experimentation and development. Â | | | | octahedron crystal faces. Cleaving is a |
| Cutting a raw diamond into a faceted and | | | | critical step as a mistake by the "cleaver" |
| polished gem-quality stone is a multi-step | | | | could shatter the stone. Â Sawing: A |
| process. Each step is critical to the final | | | | stone-cutting saw is a thin disk made of |
| outcome. The steps are: Â | | | | phosphor bronze. As the saw blade rotates it |
| | | | continues to pickup or "recharge" itself with |
| - Marking | | | | diamond dust which is the cutting agent. It |
| | | | can take several hours for the saw blade to |
| - Cleaving | | | | cut through a 1k rough diamond. Â |
| | | | Bruting: The rough is placed in a chuck on a |
| - Sawing | | | | lathe. While the rough stone rotates on the |
| | | | diamond lathe a second diamond mounted on |
| - Bruting (Girdling) | | | | adop is pressed against it, rounding the |
| | | | rough diamond into a conical shape. This step |
| - Faceting | | | | is also referred to as rounding or bruting. |
| | | | Â |
| Â Marking: A rough stone is marked prior | | | | |
| to cleaving or sawing to determine the | | | | Faceting: To facet a "Round Brilliant", a |
| direction of the grain or "cleavage", | | | | "blocker" or "lapper" will cut the first 18 |
| eliminate waste, and bypass inclusions or | | | | main facets, then a "brillianteer" will cut |
| imperfections. The natural shape of the rough | | | | and polish the remaining 40 facets. The |
| stone will also be a major factor in deciding | | | | cutting (placing) and polishing of each facet |
| how to cut the stone. An octahedron can be | | | | is accomplished by attaching the stone to a |
| cut into one or two Round Brilliants but a | | | | dop stick and pressing it against a revolving |
| square Princess cut will result in the least | | | | cast iron disk, scaife, or lap on a |
| amount of waste due to the square shape of | | | |  Facetron  that has been charged |
| the stone. Asymmetrical crystals such | | | | with diamond dust. During this faceting stage |
| asmacles are used primarily for fancy cuts. | | | | the angles of each facet must be cut to an |
| Cubic shapes are ideal for a square Princess | | | | exacting standard in order to yield maximum |
| or Radiant cut. High-tech computerizedhelium | | | | brilliancy and maintain symmetry. |
| and oxygen analizers are now used to evaluate | | | | |